Preparation Of Silicon Carbide Powder By Three Kinds Of Siliceous Waste Residue

Environmental pollution and resources shortage are two major problems restricting the development of today’s society. With the development of the industry, the waste generated in industrial production is increasing. If we want to maximize the use of resources, we must find a way to maximize the industrial wastes. This is also the most contemporary society concern. Therefore, the comprehensive utilization of industrial solid wastes become a research hotspot.This paper mainly research the preparation of SiC powder by Carbon thermal reduction process with using acid residue of fly ash, silicon powder or oil shale residue which is industrial solid wastes as raw materials. Using industrial solid wastes as raw materials will greatly reduce the generating cost, and reduce the waste of natural resources. Through the experiment research we will find the optimal conditions of preparation of SiC powder with using acid residue of fly ash, silicon powder or oil shale residue as raw materials.Then, a variety of measures was conducted to characterize the structure, morphology, chemical state and composition of the products, such as XRD, FIR and SEM, the synthetic structure and composition analysis of samples are measured.1. In order to prepare SiC powder with combination of hydro-thermal method, use acid residue of fly ash as raw materials, and the result showed that the optimal conditions is as follows:the reaction temperature is 1550℃,the holding time is 5h,the ratio of black carbon to acid residue of fly ash is 1.4:1, the amount of catalyst is 1% and holding 5h under 800 ℃ after the reaction. With the increase of the reaction temperature, the amount of SiC powder in products increase first and then keep constant. With the amount of catalyst increased, the amount of SiC powder in products increases first and then reduces.2. In order to prepare SiC powder with combination of hydro-thermal method, use silicon powder as raw materials, and the result showed that the optimal conditions is as follows:the reaction temperature is 1500℃, the holding time is 5h,the ratio of black carbon to silicon powder is 1.6:1.The temperature has a stronger influence on the generation of SiC powders.The more the temperature is.the longer SiC powders are.With the ratio of black carbon to silicon powder increased, the amount of SiC powder in products increases first and then reduces. Catalyst has a weaker influence on the preparation of SiC powders.3. In order to prepare SiC powder with combination of hydro-thermal method, use oil shale residue as raw materials, and the result showed that the optimal conditions is as follows:the reaction temperature is 1600℃, the holding time is 5h,the ratio of black carbon to silicon powder is 1.2:1.With the reaction temperature increased,the amount of SiC powder also increases. With the amount of black carbon increased, SiC powder increases first and then reduces.